From: "David Harton (dharton)" <dharton@cisco.com>
To: "Wang, Liang-min" <liang-min.wang@intel.com>,
Thomas Monjalon <thomas.monjalon@6wind.com>
Cc: "dev@dpdk.org" <dev@dpdk.org>
Subject: Re: [dpdk-dev] [PATCH 2/2] ethtool: add new library to provide ethtool-alike APIs
Date: Wed, 3 Jun 2015 01:00:07 +0000 [thread overview]
Message-ID: <E4655AD1E443BD44A5DC6E46A0FE72023178AA75@xmb-aln-x05.cisco.com> (raw)
In-Reply-To: <B6CB929FEBC10D4FAC4BCA7EF2298E2571765D45@FMSMSX110.amr.corp.intel.com>
Hi Thomas,
I think Larry explains things pretty clearly below.
A new application facing API is bring provided that avoids reusing kernel specific types and structs or dipping into the kernel itself. It also clearly separates the user space API from driver related functions/types.
We do want to limit dipping into the kernel for performance reasons.
I hope this helps,
Dave
> -----Original Message-----
> From: Wang, Liang-min [mailto:liang-min.wang@intel.com]
> Sent: Tuesday, June 02, 2015 4:56 PM
> To: Thomas Monjalon
> Cc: dev@dpdk.org; David Harton (dharton)
> Subject: RE: [dpdk-dev] [PATCH 2/2] ethtool: add new library to provide
> ethtool-alike APIs
>
> >I have the feeling we are not progressing in this discussion.
> >Please bring new explanations or I'll give up.
> >David Harton already acked it so maybe he could explain why it is useful.
> >
> >Comments below
> >
> >2015-06-02 17:06, Wang, Liang-min:
> >> >2015-06-02 15:47, Wang, Liang-min:
> >> >> From: Thomas Monjalon [mailto:thomas.monjalon@6wind.com]
> >> >> > >>I'm curious to understand how renaming rte_eth_dev_set_mtu()
> >> >> > >>to
> >> >> > >>rte_ethtool_net_change_mtu() will help anyone.
> >> >> >>
> >> >> >> As described, this interface is designed to provide API closely
> to kernel space ethtool ops and net_device_op.
> >> >>
> >> >> >But the application still needs to adapt the code to call rte_*
> functions.
> >> >> >So changing to rte_ethtool_net_change_mtu is equivalent to change
> to the existing rte_eth_dev_set_mtu. I don't see the benefit.
> >> >>
> >> >> The benefit is single interface for users to access. Instead of
> looking into two different interfaces (ethtool, ether).
> >> >
> >> >Sorry it doesn't help to understand.
> >> >Today, there is an ethdev API. Why adding an ethtool-like API would
> help?
> >>
> >> Need to understand your specific concern. Do you oppose introducing new
> API to support ethtool ops and net_device_ops?
> >
> >They are not ethtool/netdev ops but fake ones.
> >In linux:
> > int dev_set_mtu(struct net_device *dev, int new_mtu) In dpdk:
> > int rte_ethtool_net_change_mtu(uint8_t port_id, int mtu); So yes,
> I'm opposed to add an API which is neither ethdev, neither ethtool.
> >But I may be missing an obvious justification.
>
> So, the design purposely stays away from struct net_device to avoid
> carrying kernel states. We consciously choose port in place of net_device.
> The kni already provides ethtool for kernel space code, this interface is
> designed for user-space application (fast-path comparing to kni).
>
> >> Or your concern is on the implementation. If that's latter.
> >> Do you oppose adding a new library to implement ethtool ops and
> net_device_ops?
> >
> >Already answered above
> >>
> >> If so, are you satisfied with my previous answer on avoiding
> polluting ethdev APIs?
> >> If not, do you suggest integrating ethtool APIs into ethdev
> API?
> >
> >No, it's better as a separate library.
> >
> >> If not, is your concern on the implementation of common
> functionality between ethtool and ethdev APIs?
> >> If so, as explained, it is designed to provide a unified
> >> interface to assist users to migrate from kernel
> >> ethtool/net-device-op API to DPDK
> >
> >Do you mean it would help migrating some code from kernel space to dpdk?
> >How it would help since the functions and data are different from the
> kernel ones?
>
> For application that was designed based upon kernel-space ethtool-op and
> net-device-op, the user-space APIs provide a path for quick integration.
>
> >> BTW, as my reply to Steve's comment, more ops are on their way. This
> patch is to open up the interface.
> >
> >Currently they are only some one-liners plus ethtool_drvinfo formatting
> so there is no real benefit.
> >Why not wait to have more ops implemented?
> Due to amount of code change, I was advised to put into separate release
> and started with APIs that only requires minor changes on ethdev.
> The rest of API requires changes on NIC pmd driver to support ops that are
> not currently supported.
next prev parent reply other threads:[~2015-06-03 1:00 UTC|newest]
Thread overview: 43+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-05-29 19:26 [dpdk-dev] [PATCH 0/2] User-space Ethtool Liang-Min Larry Wang
2015-05-29 19:26 ` [dpdk-dev] [PATCH 1/2] ethdev: add api to set default mac address Liang-Min Larry Wang
2015-06-02 10:52 ` Ananyev, Konstantin
2015-06-02 12:23 ` Thomas Monjalon
2015-06-02 14:51 ` Stephen Hemminger
2015-06-02 15:07 ` Wang, Liang-min
2015-06-02 12:23 ` Wang, Liang-min
2015-06-02 13:10 ` Ananyev, Konstantin
2015-05-29 19:26 ` [dpdk-dev] [PATCH 2/2] ethtool: add new library to provide ethtool-alike APIs Liang-Min Larry Wang
2015-06-02 12:38 ` Thomas Monjalon
2015-06-02 13:15 ` Wang, Liang-min
2015-06-02 14:32 ` Thomas Monjalon
2015-06-02 15:47 ` Wang, Liang-min
2015-06-02 16:02 ` Thomas Monjalon
2015-06-02 17:06 ` Wang, Liang-min
2015-06-02 20:37 ` Thomas Monjalon
2015-06-02 20:56 ` Wang, Liang-min
2015-06-03 1:00 ` David Harton (dharton) [this message]
2015-06-03 2:09 ` Andrew Harvey (agh)
2015-06-04 14:25 ` O'Driscoll, Tim
2015-06-04 14:58 ` Stephen Hemminger
2015-06-04 22:10 ` Andrew Harvey (agh)
2015-06-05 10:46 ` Thomas Monjalon
2015-06-05 11:25 ` Wang, Liang-min
2015-06-05 12:47 ` Bruce Richardson
2015-06-05 17:24 ` Andrew Harvey (agh)
2015-06-05 21:03 ` Thomas Monjalon
2015-06-05 13:40 ` Thomas Monjalon
2015-06-05 14:20 ` Wang, Liang-min
2015-06-05 16:07 ` Andrew Harvey (agh)
2015-06-05 20:57 ` Thomas Monjalon
-- strict thread matches above, loose matches on Subject: below --
2015-05-30 0:37 [dpdk-dev] [PATCH 0/2] User-space Ethtool Liang-Min Larry Wang
2015-05-30 0:37 ` [dpdk-dev] [PATCH 2/2] ethtool: add new library to provide ethtool-alike APIs Liang-Min Larry Wang
2015-05-30 15:48 ` Stephen Hemminger
2015-05-30 16:16 ` Wang, Liang-min
2015-05-30 19:26 ` Stephen Hemminger
2015-05-30 19:40 ` Wang, Liang-min
2015-05-31 16:48 ` Stephen Hemminger
2015-05-31 17:30 ` Wang, Liang-min
2015-05-31 18:31 ` Wang, Liang-min
2015-06-01 12:42 ` David Harton (dharton)
2015-05-29 13:15 [dpdk-dev] [PATCH 0/2] User-space Ethtool Liang-Min Larry Wang
2015-05-29 13:15 ` [dpdk-dev] [PATCH 2/2] ethtool: add new library to provide ethtool-alike APIs Liang-Min Larry Wang
2015-05-29 15:22 ` Stephen Hemminger
2015-05-29 18:17 ` Wang, Liang-min
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=E4655AD1E443BD44A5DC6E46A0FE72023178AA75@xmb-aln-x05.cisco.com \
--to=dharton@cisco.com \
--cc=dev@dpdk.org \
--cc=liang-min.wang@intel.com \
--cc=thomas.monjalon@6wind.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).